The harm principle holds that the actions of individuals should only be limited to prevent harm to other individuals. John Stuart Mill articulated this principle in On Liberty, where he argued that,provided his acts are not invasive of the free acts of others" has become one of the basic principles of libertarian politics.

A hammermill is a mill whose purpose is to shred or crush aggregate material into smallerThe basic principle is straightforward. A hammermill is essentially a steel drum containing a vertical or horizontal rotating shaft or drum on which hammers are